Oil on all 4 plugs

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magg
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Bike owned: VFR400
Location: Blue Mountain NSW Australia

Re: Oil on all 4 plugs

Post by magg » Sun Jun 02, 2013 11:10 pm

With a battery voltage so low you would not be able to start the bike and I doubt the engine would run correctly. Your voltage measurements are reliable?

Does your bike have a vacuum fuel tap, if so, NO fuel should flow without engine vacuum wihen the tank off the bike.

Neosophist
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Re: Oil on all 4 plugs

Post by Neosophist » Mon Jun 03, 2013 11:36 am

SmallFrowne wrote:Thanks for the replies. Just had another go at it, checked voltages at 5.5k rpm as per RO's guide, which was quite hard keeping it there due to the misbehaviour, really didn't like being above idle.

The reading across the battery was between about 5.9v and 7 and a bit. Which didn't look too great. According to the guide this could indicate 2 bad coils. Time for more searching and probably get a pair of coils then, but is there any other reason for a bad voltage reading, or why 2 coils could pack up at once, like a bad reg/rect?
Cheers
That is wrong somewhere.

You have taken wrong readings or something is set wrong.

NOTHING you have shown yet says that the coils are bad.

5.9v will not start a bike.

Have you done what I said and checked all 4 plugs are sparking by looking at them?

This doesnt require a running bike, and while not 100% conclusive will be a good start ot prove that you have or do not have spark.
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

SmallFrowne
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Re: Oil on all 4 plugs

Post by SmallFrowne » Wed Jun 05, 2013 10:38 pm

Sorry, been unable to do much with the bike past few days. To clear up:

What i meant to say last time was that the voltage reading was with the bike running at 5500rpm. But... I did misread the charging system guide (http://www.400greybike.com/files/Chargi ... Checks.doc) first time through, and you are right, ignition coils are probably fine (or at least nothing to suggest otherwise, and yeah I've just double checked sparks on all 4 plugs 8-) ).

So after re-reading the guide it turns out i meant alternator coils. The alternator is probably only running on 1 phase, the regulator/rectifier has probably killed it. The connector blocks for the alternator look brown and burnt, as does the reg/rec connector. So then, the next thing is to get another generator and a new reg/rec. I've not actually checked the reg/rec yet, but probably best to get a new one anyway as it is known to f**k things up!

I have checked the yellow wires from the alternator as per the service manual. Checking the ohm reading it was about 8ohms - 11ohms from one wire to another, when the manual states 0.1-1.0 ohms is acceptable.

I've taken more pictures of the plugs, but if they look fine maybe i was just panicking and thinking it was oil (not on the tips though, which just look a bit dark as you say). If I can run the bike with alternator disconnected and purely off the battery (total loss style), that will prove everything else is ok right? Or do you need the extra juice from a (working) alternator? Wish i hadn't took the alternator cover off now, I could try it but oil would fly everywhere, maybe tomorrow...
Thanks, I'll keep this updated with what happens when i get the flywheel off and new generator on.

magg
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Joined: Mon Sep 20, 2010 11:55 pm
Bike owned: VFR400
Location: Blue Mountain NSW Australia

Re: Oil on all 4 plugs

Post by magg » Wed Jun 05, 2013 11:26 pm

Before yoy replace the alternator and/or the rect/reg, suggest you ensure the wiring/connectors between the alternator and the rect/reg is in good condition. Many NC30s have suffered from poor connectios/wiring that can result in resistance readings similar to yours

Where precisely did you measure the 8-11 ohms and what was the battery voltage after your remeasurement.

Morespeedvicar
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Re: Oil on all 4 plugs

Post by Morespeedvicar » Thu Jun 06, 2013 12:40 am

As magg says dont just dive in take your time and investigate, theres another plug on the right and side of the bike, think its just above the clutch, check that to see if the connections are good and meter it there aswell.
Cheers
Ian

SmallFrowne
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Re: Oil on all 4 plugs

Post by SmallFrowne » Sat Jun 15, 2013 3:18 pm

Yes you were right about bad readings from the connector, but sadly the alternator was still faulty. I ended up cutting the plug off to get to the 3 wires straight from alternator as it really was bad. Ohm reading was less but I also checked continuity to ground, which i hadn't before (trying to be more thorough now!), continuity existed! So I have still gone ahead and replaced it.
I do not have another reg/rec yet, but thought I'd fire it up on just the battery after reading that some track bikes do this, to at least see if it will run ok now. So leaving the new alternator wires disconnected it started.. great.. idling.. great... a few revs.. doh! Still not running right, like it's struggling to rev, maybe i can get a video up hmm. Going to recheck the valve clearances next but I'm still worried about the plugs having oil (or at least what i think is oil, it is black and wet) around the base and a few threads but not behind the washer (so surely not coming from above - plug holes look dry too), can someone please put my mind at ease if this is normal :grin: . 4 brand new plugs in now. Another picture, this is one of the new ones that has been in and out:

Image

Cheers for the help, dying to get it back on the road now!

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